Which of the following does not occur in a photoreceptor during exposure to light?
A)Membrane hyperpolarization
B)Closure of Na+ channels in the outer segment
C)Increased neurotransmitter release from the synaptic terminal
D)Decrease in cyclic GMP in the outer segment
E)Closure of Ca₂₊ channels in the synaptic terminal

Question

Quizplus · Accepted Answer

Exposure to light causes a decrease in neurotransmitter release from the photoreceptor's synaptic terminal, not an increase. This is because when light hits the photoreceptor, it leads to hyperpolarization of the membrane and a decrease in neurotransmitter release. This decrease in neurotransmitter release signals to downstream cells, such as bipolar cells and ganglion cells, that light is present. Therefore, choice C is the correct answer as it describes an incorrect response.

Which of the Following Does Not Occur in a Photoreceptor